1. Field of the Invention
The present invention relates to a bridge which connects between an expansion bus of a primary system and that of a secondary system, an error notification method for the bridge and a system.
2. Description of the Related Art
In an apparatus such as a multifunctional peripheral, copying machine, and printer, an expansion card is connected to an expansion I/F for expanding the functions of the apparatus. When a function which is not provided for the main body is added, it is often the case that the expansion I/F comprises a PCI bus or I/F corresponding to PCI. This facilitates choice of a functional device by using a PCI bus and I/F corresponding to PCI. A function which is not provided for the above-described main body includes, for example, a network function, wireless LAN function, and USB HUB function.
A method in which a function of recognizing a bus error is provided on the bridge device side, and an error notification can be performed when communication between an expansion card and main body is not established, has been conventionally proposed for notification of errors in a system using the above-described I/F (e.g., see Japanese Patent Laid-Open No. 7-210471).
In such a prior art, however, an error of a CPU local bus of an expansion card existing on the rear stage of a PCI bus on the expansion card side cannot be notified.
For this reason, time-out processing has to be used on the main body side for such local errors and a long time is taken to perform error processing after the occurrence of the error.